I'm working on a little project. I have an arduino Uno (at the moment) controlling two servos that move a big Santa. The Santa moves certain ways as you get closer to him. Kinda creepy, I know...

One of the servos moves his arm, but I noticed that when the arm is in the bottom position and resting against a physical stop, if you bump the arm, the servo starts making noise. I'm assuming that the "encoder" is sensing that the servo arm is a hair off, and is attempting to compensate. It happens with my RC airplanes all the time- it goes away when you bump the control stick or it will just settle out on its own. But in this case, the servo isn't settling out unless you cause the arm to "cycle" by standing in front of the sensor that controls the whole thing. This could be dangerous if I leave it on unattended. I'm worried that the servo will "come on" and burn up, possibly catching fire.

Would it make sense to put a transistor between the voltage regulator and servo wire? Then I could have the arduino turn off the power output to the servo when it should be at rest. I have absolutly zero experience with transistors- I just read about them in my "Getting Started with Arduino" book. Are there transistors that can handle a 400ma 6V servo? Thanks!

I've been into RC airplanes for a long time and have about 100 of them sitting around. Just out of curiosity, do you have a better solution? The hobby servo just seems so convenient since it's already in a complete assembly and only has three wires, power, gnd, and signal.